Vacuum handling method for small load units



Oct. 14, 1969 0, s, 55

VACUUM HANDLING METHOD FOR SMALL LOAD UNITS Original Filed Feb. 4, 1964 2 Sheets-Sheet l INVENTOR. O 6 0444/88 Oct. 14, 1969 o. s. CARLISS 3,471,989

VACUUM HANDLING METHOD FOR SMALL LOAD UNITS Original Filed Feb. 4, 1964 2 Sheets-Sheet 2 WC TIL 5 E1.

LWENTOR. O5 OWL/6s United States Patent 3,471,989 VACUUM HANDLING METHOD FOR SMALL LOAD UNITS I Oswald S. Carliss, Rydal, Pa., assignor to Eaton Yale &

ABSTRACT OF THE DISCLOSURE A method of utilizing vacuum to handle small load units without requiring a large container. The small load units are stacked in a pile and a single sheet of nonporous material is bound to one surface of the pile by straps encircling the pile vertically so as to form a unitized load. The sheet is applied while arranging it so that it does not extend on opposed sides of the pile, thus leaving the sides uncovered. If desired, the sheets may be applied also to the bottom of the pile, the sheets in that case being L-sh-aped. A vacuum gripper then is applied to the vertical part of the sheet so as to support and to lift the load.

This application is a continuation of my earlier application Ser. No. 342,348, filed Feb. 4, 1964, and now abandoned.

My invention rel-ates to the handling of a plurality of small cartons or load units by a vacuum operated load gripping attachment of a lift truck.

In US. Patent No. 2,942,745, there is shown a vacuum attachment for a lift truck which incorporates a plurality of vacuum cups for gripping and supporting a load. Such an attachment is very useful for handling large cartons or other unit loads having available relatively large, nonporous surfaces which the vacuum cups may grip. A vacuum cup attachment of this type, however, cannot handle a plurality of small cartons or load units, as those skilled in the art fully appreciate.

It has been suggested that small cartons or other small load units be packed in a large carton to be handled by the vacuum attachment. This requires an expensive larger carton, and time consuming and costly handling of individual cartons in packing and removing the individual cartons from the larger carton.

It has also been suggested that small cartons and packages 'be placed in an air impervious envelope and that a vacuum or suction cup be applied to an opening in the envelope to evacuate all the air in the envelope to unitize the load and the unitized load then be lifted and supported by the vacuum cup. Such a system, however, requires from five to twenty-five seconds to evacuate the air from the envelope, thereby increasing the time necessary to handle the load. Further, the air impervious envelope is quite expensive and is subject to being torn or damaged resulting in dropping of the load and preventing further use of the envelope in handling the load until it is repaired. In addition, certain goods will not withstand the pressure applied thereto by the application of vacuum to the envelope with the result that the goods may be actually crushed.

My invention represents a complete departure from the prior art for the handling of a plurality of small cartons or load units by a vacuum cup gripping attachment. Thus, in accordance with my invention, I stack the individual load units in a substantially uniform pile and secure, as by strapping, a substantially non-porous plate or sheet to one side of the pile. I am then able to handle the in- 3,471,989 Patented Oct. 14, 1969 dividual load units as a single unit by vacuum cups ap plied to the non-porous sheet.

More in detail I can use a generally L-shaped carrier or pallet formed of thin, relatively stiff, non-porous material, such a stilt cardboard or corrugated paperboard, and strap the pile of cartons to both the horizontal base portion and the vertical portion of the L-shaped carrier. The pile of individual load units may then be handled as a single load unit by applying the vacuum cup grippers of the load gripping attachment to the surface of the vertical portion of the L-shaped carrier.

Thus, with my method, only an inexpensive piece of cardboard or corrugated paperboard and straps are required for handling a large number of small cartons or load units by the vacuum cup gripper, and the small cartons may be quickly and easily removed from the carrier by cutting or removing the straps. Further, when the L- shaped carrier is not in use, it may be folded fiat to facilitate storage or return shipment.

As a feature of the invention, a second L-shaped carrier member may be used to cover two other sides of the stacked individual load units to provide additional protection for the units.

As a still further feature of this invention, the front edge of the horizontal portion of the L-shaped carrier may be turned up to provide greater resistance to transverse bending of the horizontal portion under the weight of the load.

I have thus outlined rather broadly the more important features of my invention in order that the detailed description thereof that follows may be better understood, and in order that my contribution to the art may be better appreciated. There are, of course, additional features of my invention that will be described hereinafter and which will form the subject of the claims appended hereto.

FIG. 1 is a side elevational view showing a plurality of small cartons which have been unitizedinto a single load unit in accordance with the invention, and show ing the unitized load being handled by a vacuum cup lifting attachment of a lift truck,

FIG. 2 is a perspective view of the unitized load shown in FIG. 1,

FIG. 3 is a perspective view of an L-shaped pallet used in unitizing the small cartons into a single load unit as shown in FIGS. 1 and 2,

FIG. 4 is a side elevational view of a unitized load, similar to that shown in FIGS. 1 and 2, but including a second L-shaped pallet covering two additional sides of the load unit,

FIG. 5 is a perspective view of the two L-shaped pallets used in unitizing the load as shown in FIG. 4,

FIG. 6 is a side elevational view of a unitized load, similar to that shown in FIG. 4, except that the free ends of the horizontal legs of the L-shaped pallets "are turned up to provide additional rigidity against transverse bending of the legs, and

FIG. 7 is a perspective view of the two L-shaped pallets used in unitizing the load as shown in FIG. 6.

Referring to the drawings and in particular to FIG. 1, a plurality of small load units or cartons 10, which have been formed into a single load unit in accordance with the invention, are shown being lifted and supported by. a vacuum cup load gripping attachment 11 which is mounted on a vertically movable load carriage 12 of a conventional lift truck 13.

In accordance with the invention, the plurality of small cartons 10 are formed into a single load unit by stacking the cartons 10 in a substantially uniform pile and by binding the pile of cartons together and to a sheet 14 of relatively rigid, substantially non-porous material, such as corrugated paperboard, which has been placed against a vertical side of the pile of cartons. When so unitized, the individual cartons may be handled as a single load unit by applying the vacuum cup of the load gripping attachment 11 to the outer surface of the sheet 14 and the load lifted from the ground by elevation of the load carriage 12 as shown in FIG. 1. When lifted, the unitized load unit is prevented from swinging inwardly toward the truck by an abutment pad 16 provided at the lower end of attachment 11 which engages the lower outer surface of the sheet 14.

In a preferred form of the invention, the sheet 14 forms the vertical leg of a generally L-shaped pallet or carrier 17, best shown in FIG. 3. In utilizing the pallet 17, the individual cartons 10 are stacked in a substantially uniform pile on the horizontal leg 18 of the pallet, and the pile of cartons then strapped to both the vertical leg or sheet 14 and the horizontal leg 18 of the pallet 17 by transversely spaced straps 19 and which extend over and around the pile of load units 10 and around both the vertical leg 14 and the horizontal leg 18 of the pallet, as best shown in FIG. 2. A third strap 21 may also be applied at right angles to'the straps 19 and 20 to extend over the pile of cartons and under the horizontal leg 18 to further prevent sidewise displacement of the individual cartons. In lifting the load so formed, the vacuum cup 15 is applied to the outer surface of the vertical leg or sheet 14, between the straps 19 and 20, as shown in FIG. 2.

Referring now to FIGS. 4 and 5, a second pallet 17a, identical to the pallet 17, may be used to cover two additional sides of the pile of individual cartons or load units 10 to provide additional protection to the units. Thus, for example, the second pallet 17a may be used when handling trays 10a of canned goods, as shown in FIG. 4. When the second pallet 17a is used, the straps 19 and 20 also extend over the horizontal and vertical legs 14a and 18a of the pallet 17a and the strap 21 also extends over the horizontal leg 18a of the pallet 17a.

Referring now to FIGS. 6 and 7, there is shown a slightly modified form of pallet 17b which may be used in handling heavier load units. In this modified form of pallet 17b, the free end of the horizontal leg 18b is turned up as indicated at 180 to thereby provide a greater resistance to transverse bending of the horizontal leg under the load. The pallet 17b may be used alone, or a second identical pallet 170 may be used to cover two additional sides of the load as shown in FIGS. 6 and 7. The pallets 17b and 170 are applied to the stack of load units in the same manner as described in connection with the pallet 17b shown in FIG. 4.

From the preceding description it can be seen that there is provided a novel method of handling a plurality of small load units which allows the small load units to be very quickly and inexpensively unitized into a single load unit for handling by a vacuum cup of a vacuum cup load gripping attachment. The invention further permits the individual load units to be quickly and easily removed from the simple pallet or carrier by merely cutting the retaining straps, and the pallet may be folded fiat for return shipment or storage.

I now claim:

1. A method of vacuum handling a relatively large number of relatively small load units without first enclosing the units in a large container, that includes the steps of stacking said units into a pile with the units resting against one another and upon one another, while arranging a series of said units to form the pile with one vertical surface that lies in a plane, applying against said vertical surface one leg of an L-shaped sheet of substantially non-porous thin fiat material, applying the other leg of said L-shaped sheet against the bottom surface of the pile, while arranging said legs of the sheet to leave exposed at least two opposed side surfaces of said pile, placing a flexible member about the pile, securing the flexible member in position engaging the legs of the Lshaped sheet at said vertical and bottom surfaces of the pile and extending across the load units at further surfaces of the pile whereby to bind the load units of the pile to said sheet, applying a vacuum cup gripper to the outer surface of said one leg of the L-shaped sheet in a manner to grip the said sheet, and lifting said gripper so as to lift said sheet together with the small load units.

2. A method as set forth in claim 1, in which the application of said one leg of the sheet against the vertical pile surface comprises placing said one leg to extend substantially across the units of said series of units, so as to contribute a relatively large uninterrupted surface for coaction with the vacuum cup gripper.

References Cited UNITED STATES PATENTS 2,675,123 4/1954 Baird 53-26 X 2,942,745 6/ 1960 Horton. 3,118,554 1/ 1964 Brainard et al.

FOREIGN PATENTS 1,081,823 5/1960 Germany.

OTHER REFERENCES Modern Materials Handling, Damage Free Vaccum, December 1962, pp. 58 to 63.

THERON E. CONDON, Primary Examiner R. L. SPRUILL, Assistant Examiner US. Cl. X.R. 53-26, 198; 206-; 214-650; 294-64 

